This can be proven for any valid argument form using a truth table which shows that there is no situation in which there are all true premises and a false conclusion.
Founded in 1994, IntraLearn Software Corporation (ISC) is a pioneer of creating e-Learning and Knowledge Organization products for corporate enterprises, academic institutions, associations, government agencies and training suppliers.
The Postal Service established International Service Centers (ISCs) in 1996 to become more competitive in the international mail market. ISCs distribute and dispatch both incoming and outgoing international mail. The ISC network has facilities located in five major cities: New York, Miami, Chicago, Los Angeles, and San Francisco. The Postal Service hoped that ISCs would improve service and provide the structure needed to support new products and increase revenue.